Parse table literals

This commit is contained in:
Joscha 2022-11-18 13:25:07 +01:00
parent ee832588ac
commit 1d02ff4480

View file

@ -1,7 +1,7 @@
use chumsky::prelude::*; use chumsky::prelude::*;
use chumsky::text::Character; use chumsky::text::Character;
use crate::ast::{Ident, NumLit, NumLitStr, Space}; use crate::ast::{Expr, Ident, Lit, NumLit, NumLitStr, Space, StringLit, TableLit, TableLitElem};
use crate::span::Span; use crate::span::Span;
type Error = Simple<char, Span>; type Error = Simple<char, Span>;
@ -21,7 +21,7 @@ fn ident() -> impl Parser<char, Ident, Error = Error> {
text::ident().map_with_span(|name, span| Ident { name, span }) text::ident().map_with_span(|name, span| Ident { name, span })
} }
fn num_lit_str_radix(radix: u32) -> impl Parser<char, (i64, NumLitStr), Error = Error> { fn num_lit_str_radix(radix: u32) -> impl Parser<char, (i64, NumLitStr), Error = Error> + Clone {
// Minimum amount of digits required to represent i64::MAX. The rest of this // Minimum amount of digits required to represent i64::MAX. The rest of this
// code assumes that any value that can be represented using this amount of // code assumes that any value that can be represented using this amount of
// digits fits into an u64. // digits fits into an u64.
@ -71,13 +71,63 @@ fn num_lit_str_radix(radix: u32) -> impl Parser<char, (i64, NumLitStr), Error =
}) })
} }
fn num_lit() -> impl Parser<char, NumLit, Error = Error> { fn num_lit() -> impl Parser<char, NumLit, Error = Error> + Clone {
(just("0b").ignore_then(num_lit_str_radix(2))) (just("0b").ignore_then(num_lit_str_radix(2)))
.or(just("0x").ignore_then(num_lit_str_radix(16))) .or(just("0x").ignore_then(num_lit_str_radix(16)))
.or(num_lit_str_radix(10)) .or(num_lit_str_radix(10))
.map_with_span(|(value, str), span| NumLit { value, str, span }) .map_with_span(|(value, str), span| NumLit { value, str, span })
} }
pub fn parser() -> impl Parser<char, NumLit, Error = Error> { fn string_lit() -> impl Parser<char, StringLit, Error = Error> {
num_lit().padded().then_ignore(end()) // TODO Parse string literals
filter(|_| false).to(unreachable!())
}
fn table_lit_elem(
expr: impl Parser<char, Expr, Error = Error> + Clone,
) -> impl Parser<char, TableLitElem, Error = Error> {
let positional = expr
.clone()
.map(|value| TableLitElem::Positional(Box::new(value)));
let named = ident()
.then(space())
.then_ignore(just(':'))
.then(space())
.then(expr)
.map(|(((name, s0), s1), value)| TableLitElem::Named {
name,
s0,
s1,
value: Box::new(value),
});
positional.or(named)
}
fn table_lit(
expr: impl Parser<char, Expr, Error = Error> + Clone,
) -> impl Parser<char, TableLit, Error = Error> {
let elem = space()
.then(table_lit_elem(expr))
.then(space())
.map(|((s0, elem), s1)| (s0, elem, s1));
let trailing_comma = just(",").ignore_then(space()).or_not();
let elems = elem.separated_by(just(",")).then(trailing_comma);
just("'{")
.ignore_then(elems)
.then_ignore(just("}"))
.map_with_span(|(elems, trailing_comma), span| TableLit {
elems,
trailing_comma,
span,
})
}
pub fn parser() -> impl Parser<char, TableLit, Error = Error> {
let expr = num_lit().map(|n| Expr::Lit(Lit::Num(n)));
table_lit(expr).padded().then_ignore(end())
} }